Liam ERD is an open-source tool that solves a persistent developer pain point: keeping database documentation up to date. Instead of manually drawing entity-relationship diagrams that become stale the moment a schema changes, Liam reads your actual database schema files and generates interactive, visually polished ER diagrams automatically. It supports multiple schema formats including Rails schema.rb, PostgreSQL dumps, Prisma schema files, and raw SQL — covering the most common ways developers define their database structures.
The generated diagrams are genuinely interactive: you can click on tables to see column details, follow relationships between entities, search for specific tables, and zoom into complex areas of your schema. The visual design is notably better than typical auto-generated diagrams, with clean layout algorithms that minimize crossing lines and group related tables. A web version at the project's website lets you generate diagrams from public GitHub repositories with zero setup — just paste a repository URL and get an instant visualization of the database schema.
For private repositories and CI/CD pipelines, the CLI tool generates diagrams as part of your build process, ensuring that documentation stays synchronized with schema changes automatically. With over 4,800 GitHub stars and Apache-2.0 licensing, Liam ERD fills a gap between heavyweight database design tools like DBeaver or pgAdmin and manual diagramming in tools like dbdiagram.io. For teams doing code reviews that involve schema changes, having an auto-generated visual diff of the database structure adds valuable context to pull requests.
